RESUMEN
Environmental monitoring has demonstrated widespread occurrence of the flame-retardant tris(1,3-dichloro-2-propyl) phosphate (TDCIPP), raising concerns about the impact on aquatic life. Using 1H NMR and GC-MS metabolomics and 20-day body length experiments, we have determined that exposure to TDCIPP affects Artemia franciscana. The LC50 for a 48â¯h TDCIPP exposure was determined to be 37.1⯱â¯1.3⯵M. Acute exposure (48â¯h) to 20.0⯵M did not affect A. franciscana body length but did elicit a metabolic change. Chronic exposure to 0.50⯵M TDCIPP caused decreased body length in A. franciscana exposed for 20â¯days and elicited a metabolic response. Principal component analysis revealed variance between acute and chronic exposure along PC1 (36.4%) and between control and TDCIPP along PC2 (17.4%). One-way ANOVA indicated that 19 metabolites were significantly affected by TDCIPP exposure; namely metabolites of the osmolyte class, including betaine, phosphocholine, gadusol, taurine, glycerol and trehalose - metabolites that are essential osmoprotectants in extremophile species. Other pathways that may be perturbed by TDCIPP exposure include one carbon, glycine, serine, threonine, and glycerophospholipid metabolism.
Asunto(s)
Artemia/fisiología , Compuestos Organofosforados/toxicidad , Osmorregulación/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , AnimalesRESUMEN
Global salinization trends present an urgent need for methods to monitor aquatic ecosystem health and characterize known and emerging stressors for water bodies that are becoming increasingly saline. Environmental metabolomics methods that combine quantitative measurements of metabolite levels and multivariate statistical analysis are powerful tools for ascertaining biological impacts and identifying potential biomarkers of exposure. We propose the use of the saltwater aquatic crustacean, Artemia franciscana, as a model organism for environmental metabolomics in saltwater ecosystems. Artemia are a good choice for ecotoxicity assays and metabolomics analysis because they have a short life cycle, their hemolymph is rich in metabolites and they tolerate a wide salinity range. In this work we explore the potential of Artemia franciscana for environmental metabolomics through exposure to the broad-spectrum herbicide, glyphosate. The LC50 for a 48 h exposure of Roundup® was determined to be 237 ± 23 ppm glyphosate in the Roundup® formulation. Artemia cysts were hatched and exposed to sub-lethal glyphosate concentrations of 1.00, 10.0, 50.0, or 100 ppm glyphosate in Roundup®. We profiled 48 h old Artemia extracts using 1H NMR and GC-MS. Dose-dependent metabolic perturbation was evident for several metabolites using univariate and multivariate analyses. Metabolites significantly affected by Roundup® exposure included aspartate, formate, betaine, glucose, tyrosine, phenylalanine, gadusol, and isopropylamine. Biochemical pathway analysis with the KEGG database suggests impairment of carbohydrate and energy metabolism, folate-mediated one-carbon metabolism, Artemia molting and development, and microbial metabolism.
Asunto(s)
Artemia/efectos de los fármacos , Exposición a Riesgos Ambientales/análisis , Cromatografía de Gases y Espectrometría de Masas , Glicina/análogos & derivados , Espectroscopía de Protones por Resonancia Magnética , Estrés Fisiológico/efectos de los fármacos , Animales , Glicina/toxicidad , Herbicidas/toxicidad , Metaboloma , Metabolómica , Análisis Multivariante , Análisis de Componente Principal , Contaminantes Químicos del Agua/toxicidad , GlifosatoRESUMEN
Earthworms ( Eisenia fetida) are vital members of the soil environment. Because of their sensitivity to many contaminants, monitoring earthworm metabolism may be a useful indicator of environmental stressors. Here, metabolic profiles of exposure to five chloroacetanilide herbicides and one enantiomer (acetochlor, alachlor, butachlor, racemic metolachlor, S-metolachlor, and propachlor) are observed in earthworm coelomic fluid using proton nuclear magnetic resonance spectroscopy (NMR) and gas chromatography-mass spectrometry (GC-MS). Multiblocked-orthogonal partial least-squares-discriminant analysis (MB-OPLS-DA) and univariate analysis were used to identify metabolic perturbations in carnitine biosynthesis, carbohydrate metabolism, lipid metabolism, nitrogen metabolism, and the tricarboxylic acid cycle. Intriguingly, stereospecific metabolic responses were observed between racemic metolachlor and S-metolachlor exposed worms. These findings support the utility of coelomic fluid in monitoring metabolic perturbations induced by chloroacetanilide herbicides in nontarget organisms and reveal specificity in the metabolic impacts of herbicide analogues in earthworms.
Asunto(s)
Acetamidas/metabolismo , Líquidos Corporales/química , Herbicidas/metabolismo , Oligoquetos/química , Animales , Líquidos Corporales/metabolismo , Carnitina/biosíntesis , Metabolismo Energético , Monitoreo del Ambiente/métodos , Cromatografía de Gases y Espectrometría de Masas , Oligoquetos/metabolismo , Espectroscopía de Protones por Resonancia MagnéticaRESUMEN
An anionic self-folding deep cavitand is capable of immobilizing unmodified proteins and enzymes at a supported lipid bilayer interface, providing a simple, soft bioreactive surface that allows enzymatic function under mild conditions. The adhesion is based on complementary charge interactions, and the hosts are capable of binding enzymes such as trypsin at the bilayer interface: the catalytic activity is retained upon adhesion, allowing selective reactions to be performed at the membrane surface.
Asunto(s)
Éteres Cíclicos/química , Membrana Dobles de Lípidos/química , Proteínas/química , Resorcinoles/química , Secuencia de Aminoácidos , Aniones/química , Datos de Secuencia Molecular , Unión Proteica , Proteínas/metabolismo , Electricidad EstáticaRESUMEN
CONTEXT: Most thyroglobulin (Tg) assays have a sensitivity of 0.5-1 ng/ml. A minority of patients with undetectable T4-suppressed Tg levels have a recombinant human TSH (rhTSH)-stimulated Tg above 2 ng/ml and identifiable residual disease. OBJECTIVE: The objective was to determine whether a Tg assay with improved sensitivity could eliminate the need for rhTSH stimulation when baseline Tg is below 0.1 ng/ml. DESIGN: A retrospective study of two academic endocrine practices was conducted. POPULATION: A total of 194 patients undergoing rhTSH stimulation participated in the study. RESULTS: Of the 80 patients with Tg below 0.1 ng/ml, two (2.5%) had rhTSH-stimulated Tg above 2 ng/ml. One other patient with stimulation to 0.3 ng/ml and negative 123I scan had an ultrasound-detected malignant lymph node resected. None had 131I/123I imaging after rhTSH stimulation suggestive of local recurrence or distant metastasis. If T4-suppressed Tg was 0.1-0.5 or 0.6-2.0 ng/ml, rhTSH Tg was above 2 ng/ml in 24.2 and 82.4%, respectively. CONCLUSIONS: Patients with differentiated thyroid carcinoma and a T4-suppressed serum Tg below 0.1 ng/ml rarely have a rhTSH-stimulated Tg above 2 ng/ml, and none of these patients had 131I or 123I imaging after rhTSH stimulation suggestive of local recurrence or distant metastasis. We recommend monitoring such patients with a T4-suppressed Tg level and periodic neck ultrasonography. An increase in T4-suppressed serum Tg to a detectable level or the appearance of abnormal lymph nodes by physical or ultrasound exam should prompt further investigation.
Asunto(s)
Tiroglobulina/sangre , Neoplasias de la Tiroides/sangre , Tirotropina/farmacología , Adolescente , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Inmunoensayo , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/farmacología , Estudios Retrospectivos , Sensibilidad y EspecificidadRESUMEN
Fibroblast growth factors (FGFs) play a critical role in pituitary development and in pituitary tumor formation and progression. We have previously characterized FGF signal transduction and regulation of the tissue-specific rat prolactin (rPRL) promoter in GH4 pituitary cells. FGF induction of rPRL transcription is independent of Ras, but mediated by a protein kinase C-delta (PKCdelta)-dependent activation of MAPK (ERK). Here we demonstrate a functional role for the Rho family monomeric G protein, Rac1, in FGF regulation of PRL gene expression via an atypical signaling pathway. Expression of dominant negative Rac, but not RhoA or Cdc42, selectively inhibited FGF-induced rPRL promoter activity. Moreover, expression of dominant negative Rac also attenuated FGF-2 and FGF-4 stimulation of MAPK (ERK). However, in contrast to other Rac-dependent signaling pathways, FGF activation of rPRL promoter activity was independent of the c-Jun N-terminal kinase (JNK) and phosphoinositide 3-kinase/Akt cascades. FGFs failed to activate JNK1 or JNK2, and expression of dominant negative JNK or Akt constructs did not block FGF-induced PRL transcription. Consistent with the role of PKCdelta in FGF regulation of PRL gene expression, activation of the rPRL promoter was blocked by an inhibitor of phospholipase Cgamma (PLCgamma) activity. FGF treatment also induced rapid tyrosine phosphorylation of PLCgamma in a Rac-dependent manner. These results suggest that FGF-2 and FGF-4 activate PRL gene expression via a novel Rac1, PLCgamma, PKCdelta, and ERK cascade, independent of phosphoinositol-3-kinase and JNK.